/**
 * Copyright (c) 2011, Chicken Zombie Bonanza Project
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the Chicken Zombie Bonanza Project nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL CHICKEN ZOMBIE BONANZA PROJECT BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package ucf.chickenzombiebonanza.common.sensor;

import java.util.ArrayList;
import java.util.List;

public abstract class Sensor {
	private final List<SensorStatusListener> listeners = new ArrayList<SensorStatusListener>();
	
	private SensorStateEnum sensorState = SensorStateEnum.INACTIVE;
	
	public abstract void onPause();
	
	public abstract void onResume();
	
	public abstract void refresh();
	
	public boolean isSensorActive() {
		return sensorState == SensorStateEnum.ACTIVE;
	}
	
	public final void pauseSensor() {
	    setSensorState(SensorStateEnum.PAUSED);
	}
	
	public final void resumeSensor() {
	    setSensorState(SensorStateEnum.INACTIVE);
	}
	
	public SensorStateEnum getSensorState() {
	    return sensorState;
	}
	
	protected void setSensorState(SensorStateEnum state) {
	    SensorStateEnum beforeState = sensorState;
	    sensorState = state;
		if(beforeState != sensorState) {
		    if(SensorStateEnum.PAUSED == sensorState) {
		        onPause();
		    } else if(SensorStateEnum.PAUSED == beforeState) {
		        onResume();
		    }
		    
			for(SensorStatusListener i : listeners) {
				i.onSensorStatusChange(sensorState);
			}
		}
	}
	
	public void registerSensorStatusListener(SensorStatusListener listener) {
		if(!listeners.contains(listener)) {
			listeners.add(listener);
		}
	}
	
	public void unregisterSensorStatusListener(SensorStatusListener listener) {
		listeners.remove(listener);
	}
}
